Utility of heart rate (HR)-oxygen consumption (VO₂) method to estimate energy expenditure (EE) was studied for 5 main apple working days based on 24 hour HR recording and EE by this method partially was compared with RMR (relative metabolic rate) method currently used in Japan. Results were as follows:
1. Heart rate during the apple cultivating work were 90-110 beats per minute, that were ranked with moderate work classified by Rodahl.
2. The values of EE estimated by HR-VO₂ method in every apple working days were almost suited for that of previous reports by RMR method.
3. Comparing EE by HR-VO₂ and RMR method for an example in harvesting work, 2, 654 kcal in former was 376 kcal (16.5%) higher than latter. Correlation coefficient was 0.987 (p<0.001) between both method with EE estimated in every working contents.
4. The intense of activity in a working day from view point of daily activity index (1-EE/basal metabolism) followed the order of harvesting putting sack on≅pluking flower>thinning apple> pruning.
Consequently, estimation of EE by HR-VO₂ method was precisely reflected metabolic state in human by comparison in spite of some defects. After this it was expected to use the HR-VO₂ method instead of RMR method.

Background: Mesiodentes are the most common supernumerary teeth. The cause is not fully understood, although proliferations of genetic factors and the dental lamina have been implicated. Mesiodentes can cause delayed or ectopic eruption of permanent incisors, which can further alter occlusion and appearance. Careful attention should be paid to the position and direction of the mesiodentes because of possible damage to adjacent roots in the permanent dentition period, errant extraction in the deciduous and mixed dentition periods, and damage to the permanent tooth embryo. To avoid these complications, we applied mixed reality (MR) technology using the HoloLens® (Microsoft, California). In this study, we report on three cases of mesiodentes extraction under general anesthesia using MR technology. Results: The patients ranged in age from 6 to 11 years, all three were boys, and the direction of eruption was inverted in all cases. The extraction approach was palatal in two cases and labial in one case. The average operative time was 32 min, and bleeding was minimal in all cases. No intraoperative or postoperative complications occurred. An image was shared preoperatively with all the surgeons using an actual situation model. Three surgeons used Microsoft HoloLens® during surgery, shared MR, and operated while superimposing the application image in the surgical field. Conclusions The procedure was performed safely; further development of MR surgery support systems in the future is suggested.